we're looking for one thing. >> reporter: their adventures make up two and soon to be three seasons of the animal planet show, "finding bigfoot." why is there no good fee toe of video? >> we have photos and video of basically everything, every species known to man, but no bigfoot. >> yeah, you do. there's a photo right there. >> reporter: that famous photo and the film to go with it, known as the patterson film was taken in 1967. and to our surprise, it's no joke to the bigfoot crew. which studied it and even tried to recreate it to finally determine if it was staged. most people look at this, say this is a guy in a suit. >> well, they're wrong. this has a lot more muscle mass. when you see it in motion, there's parts of the anatomy. if you know what somebody in a costume looks like and you see that in motion, you know that really doesn't look like a person in a costume. >> reporter: they study tracks, too. >> oh, yeah. >> reporter: evidence, they say, of an unidentified, large pry mat-like beast with, you guessed it, very big feet.